The error "Failed to create boundary layer mesh" occurs.
First, due to continual improvements in meshing, make sure to use the latest version of COMSOL Multiphysics: Product Download
The mesh generator was not able to create the boundary layers. The boundary layer meshing algorithm is sensitive to the topology of the model geometry, and it might help to remove any unnecessary interior boundaries, for example. The virtual operation Ignore Faces can be used for this purpose. Also try to use the setting Handling of sharp edges: Trimming in the Boundary Layers node. Check the information in the error message for details about location and possible cause of the problem. Also see the section "Troubleshooting Boundary Layer Mesh Generation" in the COMSOL documentation.
If possible, send the model file which is causing the issue to COMSOL Technical Support.
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